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Atom:
The substance is a form of matter which have a constant chemical composition and specific properties.
Various types of atoms
Element:
Element is a pure chemical substance made up of atoms with the same numbers of protons, electrons and neutrons.
Structure of atom
- In the world, all substances are made up of certain unique elements.
- So far, \(118\) elements are identified; in nature, \(92\) elements and others are prepared by laboratories.
- Element is made up of identical, tiny particles called atoms.
- The word 'atom' is obtained from the Greek word 'atomos'. Atomos means indivisible (cannot be split or divided).
- Greek philosophers Democritus and Tamil poet Avvaiyar mentioned atoms in their writings.
- John Dolton first introduced the atomic theory, followed by J.J.Thomson and Rutherford.
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